Now, before we move on, you should know that the company making the announcement is Dr. Web, which sells anti-virus software that will protect a computer against that kind of virus. It's also important to note that many of the parties weighing in are part of a security community that makes money off selling anti-virus software.

With that in mind: Phillip Elmer-Dewitt at Fortune's Apple 2.0 blog reports that the virus exploits a JavaScript vulnerability. Oracle released a patch in 2010 and after Apple got news that the virus was spreading, it released a fix in April.

In the grand scheme of things, this doesn't seem like a huge outbreak. But, as the security experts at Sophos point out, this is the second time in a year that Apple systems have been infected with malware.

Apple's operating systems are well known for not having many problems with viruses. But as Macs become more popular, it appears hackers are writing more viruses tailored for that operating system.

"First and foremost Mac users need to be sure they have installed the latest security patches from Apple.

"Second, Mac users can no longer rely on simply updating their computers. Preventative protection is an essential defense mechanism to detect and thwart future attacks."

The virus — which gets into your computer if you visit an infected site — installs malware onto a computer and later sends information such as usernames and passwords to botnets. Dr. Web estimated that of 600,000 Macs infected, 57 percent were in the United States.

We've contacted Apple for a response, but we have not heard back. We'll update if we get one.